Ratchet-action open-end wrenches

ABSTRACT

A RATCHET-ACTION OPEN-END WRENCH OF SIMPLE AND INEXPENSIVE BUT STRUCTURALLY STRONG CONSTRUCTION HAS A FIRST JAW PIVOTALLY MOUNTED ON A HANDLE WITH A SECOND JAW PIVOTALLY MOUNTED ON THE FIRST JAW SO THAT, WHEN THE WRENCH IS ROTATED IN ONE DIRECTION, THE JAWS DRIVINGLY ENGAGE A NUT OR BOLT DISPOSED BETWEEN THE JAWS. WHEN THE WRENCH IS MOVED IN THE REVERSE DIRECTION, THE PIVOTING OF THE FIRST JAW WITH RESPECT TO THE FIRST JAW THEREBY INOND JAW TO PIVOT WITH RESPECT TO THE FIRST JAW THEREBY INCREASING THE TRANSVERSE SEPARATION BETWEEN THE JAWS AND ALLOWING THE WRENCH TO BE MOVED ABOUT THE NUT IN NONDRIVING ENGAGEMENT THEREWITH.

Sept. 21,1911 L. R. DYCK 3,606,805

RA'I'CHET-ACTION OPEN-END wnnucuns Filed July 1, 1969 INVENTOR LLOYD R.DYCK AT ORNEY United States Patent 3,606,805 RATCHET-ACTION OPEN-ENDWRENCHES Lloyd R. Dyck, 20 Skipton Court, Downsview, Ontario, CanadaFiled July 1, 1969, Ser. No. 838,225

' Int. Cl. B25b 13/28 U.S. Cl. 8191B Claims ABSTRACT OF THE DISCLOSURE Aratchet-action open-end wrench of simple and inexpensive butstructurally strong construction has a first jaw pivotally mounted on ahandle with a second jaw pivotally mounted on the first jaw so that,when the wrench is rotated in one direction, the jaws drivingly engage anut or bolt disposed between the jaws. When the wrench is moved in thereverse direction, the pivoting of the first jaw with respect to thehandle permits the second jaw to pivot with respect to the first jawthereby increasing the transverse separation between the jaws andallowing the wrench to be moved about the nut in nondriving engagementtherewith.

BACKGROUND OF THE INVENTION The present invention relates to aratchet-action openend wrench.

Open-end wrenches with fixed spaced apart jaws are well known as areopen-end wrenches in which the transverse separation between the jawscan be adjusted for the purpose of allowing such a wrench to accommodatenuts and bolt heads of different sizes. Such wrenches are, however,somewhat awkward to use if there is only limited space around the nut orbolt head for swinging the handle of the wrench. In such circumstances,it is necessary repeatedly to remove the wrench from the nut or bolthead and to replace it therearound for further tightening oruntightening of the nut or bolt. Under such circumstances, it is highlybeneficial to have a wrench with a ratchet-action.

Prior proposals for ratchet mechanisms suitable for open-end wrencheshave, however, all presented certain serious disadvantages. Forinstance, some of the previously proposed ratchet mechanisms haveinvolved the use of complex and consequently expensive structures. Otherprevious proposals have included structures having insufficient strengthto withstand the substantial stresses sometimes involved in the turningof nuts and bolts.

It is accordingly an object of the present invention to provide aratchet-action open-end wrench which is relatively simple andinexpensive in its construction and yet sufficiently strong to withstandthe substantial forces to which it is likely to be subjected during use.

SUMMARY OF THE INVENTION This and other objects are achieved inaccordance with the invention by the provision of a ratchet-actionopenend wrench which comprises a handle, a first jaw having an innerface and pivotally mounted on said handle and a second jaw having aninner face transversely separated from said inner face of said first jawand pivotally mounted on said first jaw, said inner faces of said firstand second jaws defining an open-ended nut-receiving recess therebetweenwhereby, on relative rotation of said handle and said jaws, thetransverse separation between said inner faces of said first and secondjaws varies between first and second limiting values.

In accordance with a preferred feature of the invention, a wrenchaccording thereto is usefully additionally provided with spring meansadapted to urge the aforementioned first and second jaws pivotally andtransversely towards each other.

In accordance with yet another useful and preferred feature of theinvention, the novel wrenches are also usefully constructed so that thesecond jaw and the handle are provided with opposed surfaces adapted tobe moved, on relative rotation of the jaws and the handle, intostresstransmitting engagement with each other, whereby the stressesapplied to the second jaw by the first jaw are transmitted to thehandle.

In accordance with a specific feature of the invention, a ratchet-actionopen-end wrench in accordance therewith comprises a handle, a generallyU-shaped jaw member pivotally mounted on said handle and having a firstleg with an inner face, said handle and said jaw member being providedwith opposed surfaces adapted to restrict relative rotation of saidfirst jaw and said handle and to transmit stresses therebetween, and atongue having an inner face transversely separated from and opposed tosaid inner face of said first leg of said jaw member, said tongue beingpivotally mounted on said jaw member and having an outer surface adaptedto engage an opposed surface formed on said handle to transmit stressesbetween said tongue and said handle whereby, on relative rotation ofsaid handle, said jaw member and said tongue, the transverse separationbetween said inner face of said first leg of said jaw member and saidinner face of said tongue varies between first and second limitingvalues.

In this typical construction, the aforementioned spring means mayusefully comprise a helical compression spring disposed between theaforementioned opposed surfaces of the handle and the jaw member to urgethe inner face of the first leg of the jaw member and the inner face ofthe aforementioned tongue pivotally and transversely towards each other.

A specific structure for ensuring that the stresses applied to thetongue of such a wrench by the first jaw are, in turn, applied to itshandle is hereinafter described.

It will be appreciated that, although in the following description of aspecific construction for a wrench in accordance with the invention,reference is made to the use of the wrench with a nut, all suchreferences to nuts apply equally to the heads of bolts or, in fact, toany polygonally-headed members which can be rotated using a vvrench.

DESCRIPTION OF THE DRAWINGS The invention will now be described merelyby way of illustration with reference to the accompanying drawings inwhich:

FIG. 1 is a side elevation partly in section of one embodiment of aratchet-action open-end wrench in accordance with the invention, withpart of the handle omitted and showing the wrench disposed in itsdriving or gripping position about a nut;

FIG. 2 is an elevation similar to that of FIG. 1 but showing the wrenchin its non-driving or slipping position about the nut; and

FIG. 3 is a partial and exploded perspective view of the wrench shown inFIGS. 1 and 2.

DESCRIPTION OF THE PREFFERRED EMBODIMENTS Referring to the drawings, itwill be seen that the wrench indicated generally therein at 10 comprisesa handle 12 having a generally U-shaped jaw member 14 pivotally mountedthereon by a pivot pin 16.

Referring particularly to FIG. 3, it will be seen that the jaw member 14has a first leg 18 and a bifurcated second leg 20, both legs 18 and 20being integrally formed with a partially bifurcated base web 22. Alignedholes 24 are provided through the plates of the bifurcated base web 22for the pivot pin 16 while a corresponding hole 26 is provided in a head28 integrally formed with the handle 12. The head 28 of the handle 12 isalso provided with a pair of stress-transmitting surfaces 30 and 32which are disposed at a small angle to each other. The jaw member 14 isprovided with a rearwardly directed and substantially fiat surface 34disposed between the plates of the bifurcated base web 22. Engagement ofcorresponding portions of this surface 34 with the surfaces 30 and 32serves to limit the extent of relative pivotal movement of the handle 12and the jaw member 14 as well as to transmit stresses between the handle12 and the jaw member 14 as will best be understood by reference toFIGS. 1 and 2.

The first leg 18 of the jaw member 14 is also provided with an innernut-engaging surface 36.

The wrench also comprises as an essential component thereof a second jawconstituted by a tongue 38 pivotally mounted on the jaw member 14 by apivot pin 40. Holes 42 are provided in the plates of the bifurcated baseweb 22 of the jaw member 14 for receiving the pivot pin 40 and acorresponding hole 44 is provided for the same purpose through a knob 46integrally formed with the inner end of the tongue 38.

The tongue 38 has an inner surface 48 which is opposed to andtransversely separated from the inner surface 36 of the first leg 18 ofthe jaw member 14 to define an open-ended nut-receiving recess 50therebetween. The tongue 38 also has an outer surface 52 adapated toengage an inwardly directed surface 54 of an arm 56 integrally formedwith the head 28 of the wrench and extending into the bifurcated leg ofthe jaw member 14.

In accordance with a preferred feature of the invention, the wrench 10is also provided with spring means constituted by a small helicalcompression spring 58 disposed between the surface 34 of the jaw member14 within the bifurcated base web 22 and the opposed surface 32 of thehead 28 of the handle 12. This spring 58 which serves to urge surfaces32 and 34 pivotally apart about the pivot pin 16 is retained in positionby being seated in a cylindrical recess 60 extending from the surface 32into the head 28.

The wrench 10 is constructed in accordance with a preferred feature ofthe invention in such a way that the stresses which must be withstood,during use of the wrench, by the pivot pin are reduced. For thispurpose, the tongue 38 is provided at its outer end with a reducedthickness defined by the aforementioned inner surface 48 and by an outersurface 62 joined to the outer surface 52 by a sloping surface 64. Thearm 56 is similarly provided at its outer end with a surface 66 inwardlydisplaced with respect to the surface 54 and joined thereto by a slopingsurface 68, the surfaces 54, 66 and 68 being dimensioned so as to beable to fit together with the surfaces 52, 62 and 64 respectively asshown in FIG. 1. The manner in which the interengagement of thesesurfaces serves to reduce the stresses which the pivot pin 40 mustwithstand will be more readily understood after the manner in which thewrench 10 is used has been described.

The use of the wrench 10 will now be described with reference to theunscrewing of a nut 70 from an associated male threaded member (notshown), it being assumed that the nut 70 is provided with a conventionalright hand thread. To unscrew the nut, the wrench is first placed aroundthe nut 70 so that the latter is disposed within the recess with theinner surface 36 of the leg 18 of jaw member 14 and the inner surface 48of the tongue 38 substantially parallel to each other and engagingopposite parallel side edges of the nut 70 as shown in P16. 1.

Movement of the handle 12 in the direction of the arrow 72 (FIG. 1)causes a couple to be applied to the nut 70 to cause the latter to beunscrewed, the forces being transmitted from the handle 12 to the nut 70by compressive engagement of surfaces 30 and 34 and, through the tongue38 from the arm 56 to the nut 70. When the handle 12 of the wrench 10 ismoved in the opposite direction, i.e. in the direction of the arrow 74(FIG. 2) so as not to re-tighten the nut 70, i.e. to allow the wrench toslip around the nut 70, the handle 12 pivots about the pivot pin 16. Theresultant relative rotation of the handle 12 with respect to the jawmember 14 continues against the action of the spring 58 until surface 32enters into abutting engagement with the surface 34, after which timethe jaw member 14 is also moved in the direction of the arrow 74 onfurther movement of the handle 12. During such relative rotation of thehandle 12 and the jaw member 14, the arm 56 is, however, disengaged fromits abutment with the outer surfaces 52, 64 and 62 of the tongue 38 and,as a result of the reactive force exerted on the tongue 38 by the nut70, the tongue 38 is pivoted outwardly about the pivot pin '40. Thisrelative movement of the jaw member 14 and the tongue 38 effectively increases the transverse width of the recess 50 until the surface 52 comesinto abutment with the surface 66. Since the width of the recess 50 isat this time greater than the diagonal width of the nut 70 between itsopposite corners, further movement of the handle 12 in the direction 74causes the wrench 10 to slip around the nut 70. When it is desired tohave the wrench again grip the nut 70, movement of the handle in thedirection of the arrow 74 is discontinued. At this instant, the spring58 serves to urge the surfaces 36 and 48 again into engagement withopposite side surfaces of the nut 70 so that further unscrewing movementin the direction of the arrow 72 can be made.

It will be understood that, if the wrench 10 is to be used fortightening rather than unscrewing a nut 78, it is merely necessary toreverse the position of the wrench with respect to the nut, i.e. toplace the wrench so that the leg 18 of the jaw member 14 is on theright-hand side of the nut. Similar considerations apply to the use ofthe wrench 10 with nuts and bolts having left-hand threads.

Now that the functioning of the wrench 10 has been described, the mannerin which the interengagement of the surfaces 64 and 68 serves torestrict the stresses which must be withstood by the pivot pin 40 willbe explained. Referring further to FIG. 1 and assuming that the nut 70is engaged by a male threaded member with a substantial frictionalengagement therebetween, as force is applied to the handle 12 in thedirection of the arrow 72, a reactive stress is applied by the nut 70 tothe leg 18 of the jaw member 14. This stress acts as a rotational coupleon the jaw member 14 about the pivot pin 16 urging the pivot pin 40outwardly, i.e. longitudinally away from the handle 12. This stress istransmitted to the arm 56 through the compressive engagement of surfaces64 and 68. This engagement in turn prevents too great a stress having tobe withstood by the pivot pin 40.

What I claim is:

1. A ratchet-action open-end wrench which comprises a handle, a firstjaw having an inner face and pivotally mounted on said handle at a firstpivot in proximity to a forward end of said handle, a second jaw havingan inner face transversely separated from said inner face of said firstjaw, being provided with an outer surface and with a generally forwardlyfacing surface and being pivotally mounted on said first jaw at a secondpivot, said inner faces of said first and second jaws defining anopen-ended nut-receiving recess therebetween, and a projectionintegrally formed with said handle at said forward end thereof andextending forwardly therefrom, said projection including an innersurface for compressive stress-transmitting abutment with said outersurface of said second jaw and a generally rearwardly facing surface forabutment with said generally forwardly facing surface of said secondjaw, whereby, on relative rotation of said handle and said jaws, thetransverse separation between said inner faces of said first and secondjaws varies as said jaws are moved between open and closed positionsthereof with said inner surface of said projection and said outersurface of said second jaw disposed in mutual compressivestress-transmitting abutment and with said generally rearwardly facingsurface of said projection abutting said generally forwardly facingsurface of said second jaw when said jaws are disposed in said closedposition thereof.

2. A ratchet-action open-end wrench which comprises a handle, agenerally U-shaped jaw member pivotally mounted on said handle at afirst pivot in proximity to a forward end of said handle and having afirst leg with an inner face, a bifurcated second leg transverselyspaced apart from said first leg to define therewith an open-endednut-receiving recess and a Web interconnecting said first and secondlegs of said jaw member, said handle and said jaw member being providedwith opposed surfaces adapted to restrict relative rotation of said jawmember and said handle and to transmit stresses therebetween, and atongue having an inner face transversely separated from and opposed tosaid inner face of said first leg of said jaw member, said tongue beingpivotally mounted at a second pivot on said jaw member for movement atleast partially in said bifurcated second leg thereof and having anouter surface adapted to engage an opposed surface formed on said handleto transmit stresses between said tongue and said handle whereby, onrelative rotation of said handle, said jaw member and said tongue, thetransverse separation between said inner face of said first leg of saidjaw member and said inner face of said tongue varies between first andsecond limiting values.

3. A wrench as claimed in claim 2 in which a helical compression springis disposed between said opposed surfaces of said handle and said jawmember to urge said inner face of said first leg of said jaw member andsaid inner face of said tongue pivotally and transversely towards eachother when said outer surface of said tongue engages said opposedsurfaces formed on said handle.

4. A wrench as claimed in claim 2 in which said handle is integrallyformed with a projection extending forwardly into said bifurcated secondleg for engagement of an inner surface of said projection With saidouter surface of said tongue.

5. A wrench as claimed in claim 4 in which said outer surface of saidtongue is formed with a generally forwardly facing surface and in whichsaid projection integrally formed with said handle is provided on saidinner surface thereof with a generally rearwardly facing surface adaptedto be moved, on relative rotation of said handle and said jaw member,into stress-transmitting engagement with said generally forwardly facingsurface of said tongue, whereby shear stresses applied to said secondpivot are reduced.

References Cited UNITED STATES PATENTS 2,537,838 1/1951 Logan 8l9l32,618,996 11/1952 Logan 81--913X 2,704,953 3/1955 Bartlett 8191-3 JAMESL. JONES, JR., Primary Examiner

